118 THE ACUTE SELF-LIMITED INFECTIONS 



7. All persons whose profession or duty involves 

 contact with the sick should be immunized. 



8. The general vaccination of an entire community 

 is feasible and could be done without interfering 

 with general sanitary improvements, and should be 

 urged wherever the typhoid rate is high. 



Paratyphoid Fever. There is a variety of enteric 

 fever called paratyphoid fever. This is caused by the 

 Bacillus paratyphosus, an organism closely allied to 

 the true typhoid bacillus and only separated from it by 

 its ability to ferment certain sugars and the quantity 

 of acid it produces under artificial conditions. In para- 

 typhoid fever, however, the blood will not clump 

 (agglutinate) the true typhoid bacillus but does have 

 such an action upon the paratyphoid bacillus. In 

 this form of fever the course is shorter, the attack is 

 milder, and complications are much less frequent. 

 There is usually no ulceration of Peyer's plaques and 

 therefore hemorrhage from the bowel is of extreme 

 rarity. It is nevertheless an infectious disease, entirely 

 comparable in its origin, course, transmission, and 

 epidemic character to true typhoid fever, and the same 

 precautions of disinfection must be observed. 



BACTERIUM INFLUENZA 



Influenza is also called la grippe or grip, and is an 

 acute catarrhal disease usually involving the mucous 

 membrane of the upper respiratory tract, but also 

 penetrating to the deeper parts. Its causative bac- 

 terium is the Bacterium influenza or the influenza 

 bacillus. The disease is one which appears in epidemic 



